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Top FreeRTOS articles in 2020 is a go-to resource for everything FreeRTOS, a leading real-time operating system (RTOS) for microcontrollers and small microprocessors. provides open source resources, documentation, tutorials, demonstrations, blogs, and an active FreeRTOS community that started more than 18 years ago.

Distributed freely under the MIT open source license, FreeRTOS is now downloaded every 170 seconds. FreeRTOS includes a kernel and a growing set of IoT libraries suitable for use across all industry sectors. FreeRTOS is built with an emphasis on reliability, ease of use, and offers the predictability of long-term support releases.

In this article, we count down the top FreeRTOS blog posts on for 2020.

10. Introducing FreeRTOS Long Term Support

The announcement of FreeRTOS Long Term Support (LTS) starts our countdown. Richard Barry, FreeRTOS founder, mentioned that LTS was coming in a blog entry in early 2020. LTS assures the FreeRTOS community that a contiguous set of the kernel and FreeRTOS libraries, including TCP and IoT, will be maintained for two years.

Read Introducing FreeRTOS Long Term Support.

9. Introducing the FreeRTOS Cellular Library

Ringing in at number nine is the announcement of the FreeRTOS Cellular Library now available as a FreeRTOS Labs project. This library helps users accelerate cellular adoption in cellular enabled software projects.

Read Introducing the FreeRTOS Cellular Library.

8. Using FreeRTOS on ARMv8-M microcontrollers

Walking in with a Cortex-M23 on one arm and a Cortex-M33 on the other is the number eight blog with super deep details on getting the most out of ARMv8-M. When I first read this post, I was amazed at how Gaurav Aggarwal sang his way through the sometimes treacherous waters of TrustZone, memory protection units (MPU), and floating point units (FPU). A must-read!

Read Using FreeRTOS on ARMv8-M Microcontrollers.

7. Developing LoRaWAN applications with FreeRTOS

And narrowly banding its way in at number seven is a deep dive into developing LoRaWAN applications by Gaurav Gupta. In this post, the FreeRTOS community learns how to integrate Semtech LoRa peripheral with FreeRTOS and all the way through to the cloud by means of joining a LoRa Network Server (LNS).

Read Developing LoRaWAN Applications with FreeRTOS.

6. Decrease RAM footprint and accelerate execution with FreeRTOS notifications

Lightly treading at number six is a crisp piece of engineering prose by Richard Barry. After reading this blog post, you will understand the trade-offs between the semaphore/queue pattern and the buffer/notification pattern. As Barry explains, many use cases traditionally using the semaphore/queue pattern actually can implement much faster, and frugal techniques with direct-to-task notifications.

Read Decrease RAM Footprint and Accelerate Execution with FreeRTOS Notifications.

5. Using Formal Methods to validate OTA Protocol

The blog Formal Methods to validate OTA Protocol comes in at number five. Over-the-air updates, a form of over-the-air programming, is serious business, and sending your customer bad firmware can brick systems. The popularity of this post reflects the desire to perform formal verification. Murali Talupur and co-authors lead us through it.

Read Using Formal Methods to validate OTA Protocol.

4. Security for Arm Cortex-M devices with FreeRTOS

Holding steady at position four is the popular mash-up on security, FreeRTOS, and the Arm Cortex-M. This post was written by Shebu Varghese Kuriakose, Director, Software Technology Management with Arm’s Open Source Software Group and Chairman of the Trusted Firmware Project Board. If you’re a big Cortex-M user like I am, you’ll want to read this one.

Read Security for Arm Cortex-M devices with FreeRTOS.

3. Simple Multi-core Core to Core communication using FreeRTOS message buffers

There’s nothing asymmetric about number three except for the multiprocessing with multi-core microprocessors. This post by Richard Barry gets prescriptive about implementing asymmetric multi-processing (AMP) and leads readers to the fountain for a successful implementation.

Read Simple Multicore Core to Core Communication Using FreeRTOS Message Buffers.

1 and 2. Ensuring the memory safety of FreeRTOS

And oh my a tie at number two and number one—am I trying to get out of the hard decision of choosing one post over the other by the same author? You bet! Nathan Chong does an amazing job laying out the landscape of memory safety through a C Bounded Model Checker (CBMC). In Part 1 he sets the stage and in Part 2 he breaks down typical problems in state or model checking. This pair of posts helps get readers started on understanding how FreeRTOS is continuously being tested for memory safety.

Read Ensuring the Memory Safety of FreeRTOS Part 1.

Read Ensuring the Memory Safety of FreeRTOS Part 2.

Well, that’s it for 2020! Until next time: Happy hacking and see you in the FreeRTOS Community!

Richard Elberger

Richard Elberger

Richard Elberger is an IoT Principal Technologist at Amazon Web Services. As a prolific speaker, periodic writer, and tireless embedded technology addict, he creates content and builds community for IoT and Cloud practitioners globally. Richard maintains and contributes to multiple IoT-related open source projects (FreeRTOS, meta-aws, ThingPress) which helps customers build and deliver amazing IoT solutions on AWS.